Mary Elizabeth Hallock Greenewalt papers

Musical Edition

Collection 0867

( Bulk, 1879-1950 ) 1769-1950, undated
(18.2 Linear feet ; 39 boxes, 29 volumes, 23 flat files)

Summary Information

The Historical Society of Pennsylvania
Greenewalt, Mary Elizabeth Hallock, 1871-1950.
Mary Elizabeth Hallock Greenewalt papers
Date [bulk]
Bulk, 1879-1950
Date [inclusive]
1769-1950, undated
18.2 Linear feet ; 39 boxes, 29 volumes, 23 flat files
Finding aid prepared by Mary Kirk
Language of Materials
In addition to English, the collection includes occasional materials in Arabic and French.
Mixed materials [Volume]
Mixed materials [Oversize]
Flat Files 1-23
Mixed materials [Box]
Special Note for the Musical Edition
This document is a musical finding aid; a special version of the standard finding aid for collection 0867. Series 1-4 and 7 contain musical pieces created through inspiration by the materials within their respective series. Music may take a moment to load, so please be patient if it does not play immedietly upon opening a series. These accompaniments exist to provide you, the researcher, with an emotional guide to this collection. As the text of this finding aid assists you in learning the composition of materials within each series, the musical pieces are intended to provide you with emotional insite to their respective series. More information on the pieces themselves and the composers that created them can be found within each series. This project was completed in October of 2010 thanks to funding from the Heritage Philadelphia Program. We welcome any comments you have on this edition of the finding aid. Please send them to

The audio files are in m4a format, and the video is in mp4. Apple's Quicktime software is needed to hear the music that automatically loads in each series. Controls for the music is located at the bottom of the page for each series.
Mary Elizabeth Hallock’s arrival in Philadelphia in 1882 at the age of eleven set into motion a forty-year career as a musician, inventor, lecturer, writer and political activist. Born in Beirut, September 8, 1871 to Sara (Tabet) Hallock, descendant of an aristocratic Syrian family, and Samuel Hallock, a U.S. consul, she was educated in Beirut and Philadelphia. A gifted musician, Hallock graduated from Philadelphia’s Musical Academy in 1893, and in 1897 studied piano in Vienna with Theodore Leschetizky. In 1898 in Johnstown, New York, Hallock married Dr. Frank L. Greenewalt, thirty-two years old and a physician-in-chief at Girard College. The Greenewalts had one son, Crawford, born in 1902. Greenewalt, a pianist noted for her interpretation of Chopin, began in the early 1900s to investigate how gradated colored lighting might enhance the emotional expression of music. By 1920 Greenewalt had obtained the first of many patents covering a color organ designed to project a sequence of colored lighting arranged for specific musical programs. In combining light and color as a single performance Greenewalt believed she had created a new, fine art which she named “Nourathar,” or essence of light. Although awarded eleven patents, Greenewalt spent a number of years pursuing patent infringements, finding recourse in the courts in 1932 with a judgment in her favor. Greenewalt’s professional activities also included lecturing on music and serving as a delegate to the National Women’s Party, which was instrumental in winning women’s suffrage. After retiring from the concert and lecture stage, Greenewalt published Nourathar: The Fine Art of Light-Color Playing in 1946. She died on November 26, 1950, in Wilmington, Delaware. This collection offers many examples of Greenewalt’s creative processes. Greenewalt herself arranged a good portion of correspondence which details the development and manufacture of her color console and the legal battles surrounding her patents. A photo album also documents Greenewalt’s creation of her light color console. In addition, Greenewalt left an autobiography (in draft form), a family history, copies of patents, correspondence specific to patent filings, miscellaneous personal correspondence, blue prints and drawings, copies of concert programs, news clippings, lecture and radio broadcasts manuscripts, scrapbooks, two small volumes in Arabic, and numerous brochures and pamphlets pertaining to electrical lamps and theatre lighting. Artifacts include Greenewalt’s recording of Chopin made in 1920, a gold medal awarded in 1926, copper printing plates, and experimental, painted materials.

Preferred Citation

Cite as: Mary Elizabeth Hallock Greenwalt Papers (Collection 867), The Historical Society of Pennsylvania.

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Background note

In 1867 Samuel Hallock arrived in Syria as the U.S. consul for the Palestine Syrian region. Hallock, recently awarded a United States patent for improving electrotype, had also contracted with the American Bible Society to establish a printing press in Asia Minor. A thirty-three year old widower from New England at the time of his arrival in Syria, Hallock met Sara Tabet, the fifteen-year-old daughter of Namie and Miriam Tabet, a well-to-do family in the Levantine. They were married on October 18, 1870. Mary Elizabeth, born September 8, 1871, was followed by four more children, Arthur Tabet (1872), George Bliss (1874), Ethel Fleet (1876), and Edgar Byington (1877). After the birth of her fifth child in 1877, Sara Hallock, exhibiting signs of mental illness, was sent abroad for treatment, first to England and then to the United States, where she died in Northampton, Massachusetts in 1883 at the age of twenty-eight. Hallock, to provide for his children’s upbringing and education, consigned them to the care of his relatives and friends in the United States. Greenewalt, and later her sister Ethel, were settled in the Philadelphia area while their brothers lived with relatives in New England. Ethel later married William DuPont; the DuPont family provided introductions and occasionally financial support during Greenewalt’s career as an artist and inventor. In addition, Greenewalt’s son, Crawford, married Margaretta Lammot DuPont and also served as president of the DuPont Company from 1948 to 1962.

Before her arrival in the United States in 1882 Greenewalt’s life resembled that of other well-to-do families in Beirut. As a child surrounded by servants, Greenewalt never dressed herself. At the age of six Greenewalt was enrolled in a private school run by German Deaconess Sisters where Greenewalt learned French, the official school language, as well as German. Although a child at the time of her mother’s illness and separation, Greenewalt retained memories of piano lessons from her mother and days spent playing in the brilliant sunshine of Beirut. She also recalled slighting remarks from British wives regarding her mother’s difficulty with English customs, and occasional but violent outbursts by her father.

In Philadelphia Greenewalt lived with the Quaker Heacock family and attended Chelten, their private school. As a pupil, Greenewalt displayed an aptitude for music as well as mathematics. After completing her studies at the Chelten School in 1888, Greenewalt studied piano at the Philadelphia Musical Academy, graduating in 1893. In 1897 Greenewalt traveled to Vienna to study with Theodor Leschetizky, who was noted for his teaching method emphasizing tone production. After returning from Vienna, Greenewalt married Dr. Frank L. Greenewalt, physician-in-chief at Philadelphia’s Girard College in 1898 in Johnstown, New York. They had one son, Crawford, born in 1902.

When Greenewalt launched her career in the United States in 1898, she established herself as a skilled pianist who exemplified Leschetizky’s musical training, and in 1903 edited a book on the Leschetizky teaching method by Marie Prentner. While proving herself a serious musician in the early 1900s, Greenewalt also established herself as a public speaker, sharing her musical knowledge with audiences in Philadelphia, New York, Boston, Atlanta, and Chicago. Greenewalt’s lecture titles included: “Musical Literature, The Birthdays of Queen Music,” “Sun Time and Rag Time,” “The Music of the Future,” and “”Women in Interpretive and Creative Music.” Greenewalt also addressed musical pedagogy, speaking on “The Elocution of Playing,” and “The Music Teacher in Germany,” and lecturing on Chopin, Debussy, and Liszt. In the 1920s Greenewalt also utilized radio to reach audiences. Several handwritten manuscripts concerning lectures on light-color play demonstrated Greenewalt’s approach to the unseen audience. “Are you there? Fellow Spirits across space. Are you there Mary and Lucie and Nancy and Susie and David and John? Even though I can’t see you, I know every one of you is ‘all there.’ True Blue.” Another manuscript, dated June 3, 1927, documents a radio address in German to Lankenau Hospital.

While Greenewalt’s lectures addressed different facets of music, her research interest focused primarily on the physical basis of music’s emotional appeal. Investigating the relationship between pulse and rhythm as a means of explaining this appeal led Greenewalt to publish an article titled “Pulse and Rhythm” in the Popular Science Monthly of September 1903. In 1904 the Music Teachers’ National Association invited Greenewalt to perform and to lecture on “Pulse and Rhythm in Verse and Music” at the St. Louis Exposition. In exploring music’s emotional appeal, Greenewalt turned to investigating colored lighting as the medium capable of giving expression to the combined mind and body response to music. These studies became the basis for Greenewalt’s experiments with color lighting and the many patents developed in the creation of her color organ. A prodigious and meticulous writer, Greenewalt not only documented her work but in many cases left drafts that provide insights into her creative process.

From initial experiments in 1905 with coloring photographic film, until 1919 when Greenewalt unveiled her color organ, the Sarabet (named after her mother, Sara Tabet), Greenewalt worked toward establishing a niche for herself as an artist and inventor who had discovered a unique relationship between light and music. Greenewalt’s first major step toward this goal occurred in 1916 in a light-color demonstration before the Illuminating Engineering Society of Philadelphia at the Bellevue-Stratford Hotel in Philadelphia. For this demonstration Greenewalt employed a lighting unit which illuminated rotating rolls of painted acetate-cellulose film, her “canvas” of color timed to correspond to set pieces of music. In a handwritten essay, Greenewalt described this performance as having “established a synchronism between the half tones of light and the half tones of music, not in their organic selves but in the values they both so richly hold within them.” Despite the success of this demonstration, Greenewalt recognized the need for a more precise and controlled method of displaying color gradations.

In 1918 Greenewalt filed her first patent, “Illuminating Means,” which described a timed, sequential process for controlling color and light intensities as used in a phonograph machine. As designed by Greenewalt, lamps shining through color discs emitted gradated shades of colored light in a phonograph operated, according to Greenewalt, on “the air pump principle” used “because it offers fluid control.” Greenewalt described this first patent application, and two proposed patents, in an address to the Philadelphia Illuminating Engineering Society on April 19, 1918. In her address, Greenewalt claimed that these patents represented the creation of a new art which she titled “Light: Fine Art the Sixth.” At this time Greenewalt also proposed a universal light score which might be used to indicate light gradations in the same way musical notes served in a musical scale. Greenewalt realized these aims in a 1920 patent for “Rheostats” and a 1921 patent for “Notation for Indicating Lighting Effects.” At this time Greenewalt, working with an improved rheostat design, contracted with General Electric to manufacture a color console. She also relied on the George Cutter Works of the Westinghouse Electric & Manufacturing Company to supply elements necessary for her color console. To publicize her color console, Greenewalt arranged public demonstrations for interested theatre and film house owners. In 1922 Greenewalt herself accompanied a truck driver delivering her console for a performance at the John Wanamaker store in New York.

While attempting to market her instrument, Greenewalt arranged for the manufacture of a second console for Pierre DuPont’s conservatory at Longwood, Kennett Square, Pennsylvania. Before its installation the console was demonstrated at the Pittsburgh, Pennsylvania, Calvary Episcopal Church Easter service in the Spring of 1924. In an address before the Philadelphia Illuminating Engineers Society in 1923, titled “A Light Scoring for the Episcopal Service,” Greenewalt described the console’s operation in the upcoming service, the instrument’s design, and the patents accorded this design. Greenewalt urged the engineers to support her patent claims for priority in developing a light color organ; at this time Greenewalt had begun pursuing other color organ performers for patent infringement.

Greenewalt’s achievement, which brought inquiries from as far away as Japan, also brought her into competition with others interested in exploiting light-color properties. In 1922 Thomas Wilfred performed with his color organ, The Clavilux, which projected colored light without musical accompaniment. Publicized as “Light as a fine art,” the Clavilux “made its debut at the Neighbourhood Playhouse, New York, on January 10, 1922.” That same year, Greenewalt cited Wilfred for patent infringement on her “System of Notation for Indicating Lighting Effects.” Although Greenewalt soon abandoned this suit against Wilfred, she pursued electrical product manufacturers, and theatre owners who contracted with these manufacturers, for patent violations.

Greenewalt also continued over the next decade to improve her light-color system, receiving eleven patents by 1934. Working as an individual outside of academic institutions or corporations, however, Greenewalt relied on engineers to assist with calculations for her rheostat and for preparing blueprints for manufacturing her light player and light keyboard. In her writings, Greenewalt often questioned the close ties between her patent attorneys who held retainers with the electrical companies manufacturing her consoles. As a result, the charge that powerful business and political interests prevented Greenewalt from receiving recognition and compensation for her work appears repeatedly throughout Greenewalt’s public addresses or writings. One such text from Greenewalt’s photo album states:

“It will be hard for future ages to realize how completely at this time the electric aggregations held control over practically every door of opportunity. My patent attorneys held a retainer fee from the General Electric. . . . It is unbelievable how next to impossible it was for the individual to run through the hindrances everywhere placed in his way.”

In Greenewalt’s first major suit, Greenewalt v. Stanley Company of America, 1920, Greenewalt’s own trial demonstrations, such as the 1911 Wanamaker’s Egyptian Hall performance, were cited as proof that her invention was in public use and therefore not eligible for patent protection. It was not until 1932 that Greenewalt obtained a legal victory when the courts recognized her unique contribution to the field of color-lighting. This success, however, failed to reimburse her for her financial and intellectual investments, and Greenewalt spent the next several years in an unsuccessful suit against the Musical Arts Association which operated Severance Hall in Cleveland, Ohio.

In addition to turning to the courts to protect her patent claims, Greenewalt also looked to politics to curtail the power of the electrical companies. As a member of the National Women’s Party, Greenewalt encouraged women to support Franklin D. Roosevelt and his administration’s attempts to control the power of utilities.

While Greenewalt’s color organ failed to provide financial reimbursement, publicity surrounding the color organ generated honorary awards and recognitions. As early as 1903 Thomas Eakins painted her portrait, now in the Roland P. Murdock Collection of the Wichita Museum of Art. In 1926 Greenewalt received a gold medal for her color organ in Philadelphia’s Sesqui-centennial exposition. And in 1934 the Museum of Science and Industry, in Chicago, installed Greenewalt’s color organ in their “Century of Progress” exhibit.

Greenewalt’s vision of her “fine art” expressed itself not only in her patents and commercial ventures, but also in writings expounding on light and sound and their relation to human psychology. For Greenewalt, her “fine art” offered an aesthetic and spiritual experience; she compared the light-player’s experience to “sit[ting] within a huge all-color jewel while this every colored jewel spoke the music of one’s soul… .” In her manuscript Nourathar: The Fine Art of Light-Color Playing Greenewalt laid out the aesthetic and physical principles guiding her in creating the color organ. She coined the word  Nourathar from Arabic roots meaning Nour (light) and Athar (essence of). This collection holds an unpublished 1940 manuscript of  Nourathar.

In this manuscript Greenewalt also addressed the rationale underlying color choices for musical settings. According to Greenewalt, colors possessed their “very own characteristics, idiosyncracies” [sic]. And Greenewalt speculated: “Are we driven by a might outside us? Or do we drive? I am no metaphysician. Experience furnished a valuable thread to logic. I know that in this huge labor I was driven by some weird force or push.” Greenewalt, acknowledging that the eye does not perceive every shade of color, nevertheless claimed the eye as a link to the spiritual, stating: “The eye then as the gauge; the spectral is the nearest in fineness to the spiritual essence man seeks to express through the arts. It is the most perfect. Its apportionment unto color stupendous in its portent.” In addition to finding spiritual and aesthetic links to her work, Greenewalt also suggested that her art “Nourathar,” served as a therapeutic tool for the mentally ill. The magazine, The New Delawarean, November 1939, shows the color organ installed in the Delaware State Hospital patients’ chapel.

By the late 1930s Greenewalt ceased pursuing patent infringements and demands for reimbursement for use of her light-color process. She continued to use speaking engagements and letter writing to promote her art and to remonstrate against those companies which she believed had denied her credit and reimbursement for her accomplishments. In 1942, Greenewalt’s husband Frank Lindsay died at the age of seventy-six; Greenewalt died on November 26, 1950, in Wilmington, Delaware.

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Scope and Content

The Mary Elizabeth Hallock Greenewalt Papers offer an impressive array of materials touching not only on the creative processes of an artist-inventor but also on an individual’s experience with the United States patent system. Intertwined with the story of Greenewalt’s invention of the color organ is the record of her battle for legal recognition of her right to financial gain on her patents. In addition to retaining a record of patent infringement court proceedings, Greenewalt also summarized her experiences in an unpublished 1934 manuscript, A to Z, A Compilation of Patent Letters with Letters Patent. Here Greenewalt recounted how manufacturers and theatre owners conspired to utilize her light control process without acknowledging her patents and thereby avoiding patent royalties.

Greenewalt’s papers also include an unpublished Autobiography containing memories of her early life in Syria, her father’s career, her mother’s mental illness, and Greenewalt’s emigration to the United States at age eleven. Greenewalt’s autobiographical notes contain many drafts of this work, which indicate the evolution of her thought as she worked to develop the color organ and show her appreciation for the color organ’s scientific and aesthetic properties. Other writings include Greenewalt’s manuscripts of lectures and addresses, including her radio addresses, and some family correspondence. An extensive photograph album contains color organ photos and Greenewalt’s commentary on the progress of her invention.

Other materials include a 1920 sound recording of Chopin’s works performed by Greenewalt for Columbia Records, pastel drawings and painted materials from Greenewalt’s early experiments with color and light, and many blue prints and tissue sketches of her color organ designs. Of particular interest is Greenewalt’s photo album documenting her early color-light experiments. The collection also contains several scrapbooks documenting Greenewalt’s professional life. A scrapbook devoted to her father, Samuel Hallock, contains personal correspondence pertaining to Hallock’s career and marriage, and Samuel Hallock’s electrotype patent award. There are many lighting manufacturers’ catalogs and brochures to which Greenewalt often added her commentary, reviews of performances by other light-color artists, and articles on color theory. Personal items include Greenewalt’s bridal souvenir book and the gold medal and diploma she received at the 1926 Sesqui-Centennial in Philadelphia.

The papers have been divided into seven series. Series I contains files arranged alphabetically by Greenewalt and documents Greenewalt’s efforts to create and market her invention and protect it from patent infringement. Folder titles reference correspondence with manufacturers, engineers, and theatre owners involved with the development and demonstration of Greenewalt’s color organ. Other files reference correspondence with attorneys, law suit filings, and other artists also promoting color organs. Also included are Greenewalt’s accounts of the color organ design and manufacture, and reports of color organ demonstrations. DuPont correspondence files and a file on Tabet (maternal) genealogy offer family-related references in Series I.

Series II focuses solely on Greenewalt’s color organ, offering writings and sketches concerning the color organ, as well as representative sample materials used for the organ. This series also contains Greenewalt’s 1940 unpublished manuscript, The Fine Art of Nourathar.

Series III documents Greenewalt’s legal activities and is divided into two sections, Patents and Lawsuits. The Patent files include correspondence surrounding the patent preparations as well as copies of the original patents. The Lawsuit section contains trial transcripts and correspondence concerning Greenewalt’s infringement suits. This series also contains Greenewalt’s 1934 unpublished manuscript, A to Z, A Compilation of Patent Letters with Letters Patent, which describes her legal difficulties.

Series IV includes an unpublished Autobiography in handwritten and typed form, autobiographical materials describing Greenewalt’s accomplishments, copies of her addresses and lectures, and news clippings about her activities. Also included are a Genealogy Notes and Correspondence file concerning the Hallock and Tabet families, a Family Correspondence and Clippings file, and a Miscellaneous Writings file offering what may be short stories by Greenewalt. There are also several booklets concerning Greenewalt or the Hallock family.

Series V includes printed materials about lighting manufacturing and stage lighting uses, and press clippings about James G. Blaine (1830-1893), former U.S. congressman and secretary of state.

Series VI contains Greenewalt’s photograph album recording her work and a collection of family photographs.

Series VII contains a sound recording (reformatted from phonograph to CD), printing blocks, pastel drawings, painted experimental materials, several books in French and Arabic, and Greenewalt’s awards. Included also are scrapbooks of news clippings describing Greenewalt’s early concert tours as well as her first public demonstrations of using color with music. A scrapbook devoted to Greenewalt’s parents contains letters written by her mother, letters of introduction written for her father before his appointment as U.S. consul in Syria, and the original patent awarded to Samuel Hallock for his electrotype improvements. Flat files contain blueprint and tissue drawings of Greenewalt’s color organ.

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Overview of Arrangement

Series I. General Files, 1883-1935, undated, Boxes 1-11, Flat Files 1-7

Series II. Color Organ, 1903-1943, undated, Boxes 12-13, 39, Flat Files 8-9

Series III. Legal, 1920-1936, undated

a. Patents, 1920-1934, undated, Boxes 14-17, 36, Flat File 10

b. Lawsuits, 1920-1936, undated, Boxes 18-22, 36, Flat File 11

Series IV. Writings, 1920-1950, undated, Boxes 23-25, 37, 38, Volumes 12, 18-19

Series V. Printed Materials, 1916-1935, undated, Boxes 25-27, Flat Files 12-13

Series VI. Photographs, circa 1870-1933, undated, Boxes 28-29, Volumes 4, 20, Flat File 14

Series VII. Artifacts, Scrapbooks, Paintings, Drawing, Blue Prints, 1769-1933, Boxes 30-35, Volumes 1-3, 5-17, 21-29, Flat Files 15-23

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Administrative Information

Publication Information

 The Historical Society of Pennsylvania 2008

1300 Locust Street
Philadelphia, PA, 19107

Revision Description

 Transferred from MS Word to Archivists' Toolkit and minimal corrections made by Dana Dorman, October 2010.




Gift of Mary Elizabeth Hallock Greenewalt, 1939.

Processing Note

Series I, Boxes 1-11 reflect Greenewalt’s filing arrangement. Many documents required copying; where possible, some of the originals of these documents have been placed in folders at back of each box. Due to the large number of fragile materials, there remain a number of documents that would benefit from copying.

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Related Materials

Related Materials at Other Institutions

Eakins, Thomas. Mary Elizabeth Hallock Greenewalt. Portrait, 1903. Roland P. Murdock Collection, Wichita Museum of Art.

Mary Elizabeth Hallock Greenewalt Papers, Library of Congress, Washington, D.C. Light-Color Play Console (Color Organ) at Museum of Science and Industry, Chicago, Illinois (1934).

Mary Halleck [sic] Greenewalt, Papers, 1930s-1940s. Delaware Historical Society.

Related Materials at the Historical Society of Pennsylvania

Greenewalt, M. E. H. Pulse in verbal rhythm. Philadelphia, 1905. (Call number WxG* .21 v.2)

Greenewalt, M. E. H. Time eternal: lecture delivered under the auspices of the Public Libraries of Philadelphia. Reprinted from the  Metaphysical magazine, 1906. (Call number WxG* .21 v.2)

Separation Report

Four 5” x 3” nitrate negatives in Box 35 should be put in cold storage.

The Federal Reporter, Vol. 39 (2d)-No. 1, May 26, 1930, pp. 1-296. Copy made of pp. 102-104, Greenewalt v. Stanley Co. of America. The book is in very poor condition, not salvageable.

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Controlled Access Headings

Corporate Name(s)

  • American Bible Society.
  • E.I. du Pont de Nemours & Company.
  • Eastman Kodak Company.
  • General Electric Company.
  • Westinghouse Electric & Manufacturing Company.

Personal Name(s)

  • Greenewalt, Crawford H., 1902-1993.
  • Hallock, Homan, 1803-1894.
  • Heacock, Annie, 1838-1932.
  • Wilfred, Thomas, 1889-1968.


  • Color--Therapeutic use.
  • Concert tours.
  • Music and color.
  • Musical Arts Association (Cleveland, Ohio).
  • Musical inventions and patents.
  • Musical meter and rhythm.
  • Organ (Musical instrument).
  • Patent infringement.
  • Patent suits.
  • Stage lighting.
  • Theremin.
  • Women inventors.
  • Women pianists.

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Greenewalt, Mary Elizabeth Hallock. Nourathar: The Fine Art of Light-Color Playing. Unpublished: 1940.

Greenewalt, Mary Elizabeth Hallock. Nourathar: The Fine Art of Light-Color Playing. Philadelphia: Westbrook Publishing Company, 1946.

Heacock, Annie. Reminiscences. Privately published, 1926.

Bentacourt, Michael. “Mary Hallock-Greenewalt’s ‘Abstract Films.’” Accessed September 26, 2007.

Luckiesh, Matthew. Color and Its Applications. New York: D. Van Nostrand Company, 1915. Accessed November 9, 2007.

Peacock, K. “Instruments to Perform Color Music: Two Centuries of Technological Experimentation,” Leonardo 21, no. 4 (1988): 397-406.

United States Patent and Trademark Office.

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